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51.
Cultural factors constraining the introduction of family planning among the Kassena-Nankana of northern Ghana 总被引:1,自引:0,他引:1
PB Adongo JF Phillips B Kajihara C Fayorsey C Debpuur FN Binka 《Canadian Metallurgical Quarterly》1997,45(12):1789-1804
This study presents a focus group investigation of reasons why women in a rural, Sahelian community are reluctant to adopt family planning even when convenient services are made freely available. First, women opting to practice contraception must do so at considerable risk of social ostracism or familial conflict. Implementing individual preference is something that must be done without the support of others. Second, few women view personal decisions about contraceptives as theirs to make. Women and children are the property of the corporate family-kin and community militate against reproductive control. Third, although children are highly valued for a variety of economic, social, and cultural reasons, mortality risks remain extremely high. Low fertility imposes the unacceptable risk that a woman will have no surviving children at the end of her reproductive life. Taken together, these findings attest to the inadequacy of service strategies focused on the contribution of distribution, individual agency, or personal choice. Outreach should also build a sense of community legitimacy for the program, collective health action, and traditional leadership support for family planning behavior. 相似文献
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The effect of dietary fats on the chemical composition and enzyme activities has been studied in intestinal brush border membranes (BBM) or rats. Animals were given commercial rat pellet diet (RP) or semisynthetic diet rich in either saturated [coconut oil (CCO))] or polyunsaturated [n-6, corn oil (CO) or n-3, fish oil (FO)] fat at the 10% level for 5 weeks. The membrane cholesterol/phospholipid ratio was augmented in CO- or RP-fed rats. There was an increase in level of saturated fatty acids in BBM from CCO- or FO-fed animals. n-3 polyunsaturated fatty acid content was raised in FO-fed rats, while the proportion of linoleic acid and arachidonic acid was enhanced in animals given a CO diet. Membrane fluidity was in the order of CCO < RP = CO < FO. The membrane hexose content was high (p < 0.05) in the CCO group. Hexosamines were elevated (p < 0.05) in CCO- or FO-fed rat brush borders. Membrane fucose was unaltered, while sialic acid content was elevated in CO- (p < 0.05) and FO- (p < 0.01) fed vs. CCO-fed rats. Lectin binding to brush borders corroborated these findings. The activities of alkaline phosphatase, sucrase and lactase were augmented (p < 0.001) in CCO-fed animals. Leucine-aminopeptidase and sucrase activities were depressed by FO feeding. The activities of PNP-beta-glycosidases were the highest in FO-fed rats. These results indicate that dietary fat quality markedly affects microvillus membrane lipid composition, glycosylation and enzyme functions in rat intestine. 相似文献
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FN Renaud M Dutaur S Daoud D Aubel P Riegel D Monget J Freney 《Canadian Metallurgical Quarterly》1998,36(12):3698-3702
We tested the carbon substrate assimilation patterns of 40 Corynebacterium amycolatum strains, 19 C. minutissimum strains, 50 C. striatum strains, and 1 C. xerosis strain with the Biotype 100 system (bioMérieux, Marcy-l'Etoile, France). Twelve carbon substrates of 99 allowed discrimination among the species tested. Additionally, assimilation of 3 of these 12 carbon substrates (maltose, N-acetyl-D-glucosamine, and phenylacetate) was tested with the API 20 NE identification system (bioMérieux). Since concordant results were observed with the two systems for these three carbon substrates, either identification system can be used as a supplementary tool to achieve phenotypic differential identification of C. amycolatum, C. minutissimum, and C. striatum in the clinical microbiology laboratory. 相似文献
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V Suchkova FN Siddiqi EL Carstensen D Dalecki S Child CW Francis 《Canadian Metallurgical Quarterly》1998,98(10):1030-1035
BACKGROUND: Ultrasound at frequencies of 0.5 to 1 MHz and intensities of > or =0.5 W/cm2 accelerates enzymatic fibrinolysis in vitro and in some animal models, but unacceptable tissue heating can occur, and limited penetration would restrict application to superficial vessels. Tissue heating is less and penetration better at lower frequencies, but little information is available regarding the effect of lower-frequency ultrasound on enzymatic fibrinolysis. We therefore examined the effect of 40-kHz ultrasound on fibrinolysis, tissue penetration, and heating. METHODS AND RESULTS: 125I-fibrin-radiolabeled plasma clots in thin-walled tubes were overlaid with plasma containing tissue plasminogen activator (tPA) and exposed to ultrasound. Enzymatic fibrinolysis was measured as solubilization of radiolabel. Tissue attenuation and heating were examined in samples of porcine rib cage. Fibrinolysis was increased significantly in the presence of 40-kHz ultrasound at 0.25 W/cm2, reaching 39+/-7% and 93+/-11% at 60 minutes and 120 minutes, compared with 13+/-8% and 37+/-4% in the absence of ultrasound (P<0.0001). The acceleration of fibrinolysis increased at higher intensities. Attenuation of the ultrasound field was only 1.7+/-0.5 dB/cm through the intercostal space and 3.4+/-0.9 dB/cm through rib. Temperature increments in rib were <1 C/(W/cm2). CONCLUSIONS: These findings indicate that 40-kHz ultrasound significantly accelerates enzymatic fibrinolysis at intensities of > or =0.25 W/cm2 with excellent tissue penetration and minimal heating. Externally applied 40-kHz ultrasound at low intensities is a potentially useful therapeutic adjunct to enzymatic fibrinolysis with sufficient tissue penetration for both peripheral vascular and coronary applications. 相似文献
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